diff --git a/yarn/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala b/yarn/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
index 37e98e01fddf79d823e89f62561f9ac98a785479..4cc320c5d59b5c1df357df2ea4d5c78ece5b2e15 100644
--- a/yarn/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
+++ b/yarn/src/main/scala/org/apache/spark/deploy/yarn/ApplicationMaster.scala
@@ -54,7 +54,7 @@ private[spark] class ApplicationMaster(
   private val sparkConf = new SparkConf()
   private val yarnConf: YarnConfiguration = SparkHadoopUtil.get.newConfiguration(sparkConf)
     .asInstanceOf[YarnConfiguration]
-  private val isDriver = args.userClass != null
+  private val isClusterMode = args.userClass != null
 
   // Default to numExecutors * 2, with minimum of 3
   private val maxNumExecutorFailures = sparkConf.getInt("spark.yarn.max.executor.failures",
@@ -81,7 +81,7 @@ private[spark] class ApplicationMaster(
     try {
       val appAttemptId = client.getAttemptId()
 
-      if (isDriver) {
+      if (isClusterMode) {
         // Set the web ui port to be ephemeral for yarn so we don't conflict with
         // other spark processes running on the same box
         System.setProperty("spark.ui.port", "0")
@@ -139,7 +139,7 @@ private[spark] class ApplicationMaster(
       // doAs in order for the credentials to be passed on to the executor containers.
       val securityMgr = new SecurityManager(sparkConf)
 
-      if (isDriver) {
+      if (isClusterMode) {
         runDriver(securityMgr)
       } else {
         runExecutorLauncher(securityMgr)
@@ -162,7 +162,7 @@ private[spark] class ApplicationMaster(
    * from the application code.
    */
   final def getDefaultFinalStatus() = {
-    if (isDriver) {
+    if (isClusterMode) {
       FinalApplicationStatus.SUCCEEDED
     } else {
       FinalApplicationStatus.UNDEFINED
@@ -243,7 +243,7 @@ private[spark] class ApplicationMaster(
   private def runAMActor(
       host: String,
       port: String,
-      isDriver: Boolean): Unit = {
+      isClusterMode: Boolean): Unit = {
     
     val driverUrl = AkkaUtils.address(
       AkkaUtils.protocol(actorSystem),
@@ -251,7 +251,7 @@ private[spark] class ApplicationMaster(
       host,
       port,
       YarnSchedulerBackend.ACTOR_NAME)
-    actor = actorSystem.actorOf(Props(new AMActor(driverUrl, isDriver)), name = "YarnAM")
+    actor = actorSystem.actorOf(Props(new AMActor(driverUrl, isClusterMode)), name = "YarnAM")
   }
 
   private def runDriver(securityMgr: SecurityManager): Unit = {
@@ -272,7 +272,7 @@ private[spark] class ApplicationMaster(
       runAMActor(
         sc.getConf.get("spark.driver.host"),
         sc.getConf.get("spark.driver.port"),
-        isDriver = true)
+        isClusterMode = true)
       registerAM(sc.ui.map(_.appUIAddress).getOrElse(""), securityMgr)
       userClassThread.join()
     }
@@ -427,7 +427,7 @@ private[spark] class ApplicationMaster(
     sparkConf.set("spark.driver.host", driverHost)
     sparkConf.set("spark.driver.port", driverPort.toString)
 
-    runAMActor(driverHost, driverPort.toString, isDriver = false)
+    runAMActor(driverHost, driverPort.toString, isClusterMode = false)
   }
 
   /** Add the Yarn IP filter that is required for properly securing the UI. */
@@ -435,7 +435,7 @@ private[spark] class ApplicationMaster(
     val proxyBase = System.getenv(ApplicationConstants.APPLICATION_WEB_PROXY_BASE_ENV)
     val amFilter = "org.apache.hadoop.yarn.server.webproxy.amfilter.AmIpFilter"
     val params = client.getAmIpFilterParams(yarnConf, proxyBase)
-    if (isDriver) {
+    if (isClusterMode) {
       System.setProperty("spark.ui.filters", amFilter)
       params.foreach { case (k, v) => System.setProperty(s"spark.$amFilter.param.$k", v) }
     } else {
@@ -491,7 +491,7 @@ private[spark] class ApplicationMaster(
   /**
    * An actor that communicates with the driver's scheduler backend.
    */
-  private class AMActor(driverUrl: String, isDriver: Boolean) extends Actor {
+  private class AMActor(driverUrl: String, isClusterMode: Boolean) extends Actor {
     var driver: ActorSelection = _
 
     override def preStart() = {
@@ -503,7 +503,7 @@ private[spark] class ApplicationMaster(
       driver ! RegisterClusterManager
       // In cluster mode, the AM can directly monitor the driver status instead
       // of trying to deduce it from the lifecycle of the driver's actor
-      if (!isDriver) {
+      if (!isClusterMode) {
         context.system.eventStream.subscribe(self, classOf[RemotingLifecycleEvent])
       }
     }
@@ -513,7 +513,7 @@ private[spark] class ApplicationMaster(
         logInfo(s"Driver terminated or disconnected! Shutting down. $x")
         // In cluster mode, do not rely on the disassociated event to exit
         // This avoids potentially reporting incorrect exit codes if the driver fails
-        if (!isDriver) {
+        if (!isClusterMode) {
           finish(FinalApplicationStatus.SUCCEEDED, ApplicationMaster.EXIT_SUCCESS)
         }